Eric Christian Olsen: Fatherhood Has Turned Me Into a ‘Softie’

Eric Christian Olsen and wife Sarah Wright had a big baby on their hands from the beginning — son Wyatt Oliver was 9 lbs., 8 oz. when he arrived in August. And he’s only been getting bigger since then.

“We have the most giant baby of all time,” the NCIS: Los Angeles star, 36, marveled to PEOPLE Monday at TV Guide‘s Hot List Party in Hollywood.

Wyatt may be a handful physically, but Olsen says it’s the emotional intensity of fatherhood that was the biggest surprise to him.

“I’m such a sucker for that kid when he smiles,” he says. “He squints his eyes and he gets this big gummy smile, and it’s just emotions I didn’t know I had. I’ve become such a softie. I get tears in my eyes, and I get all excited. It’s just that’s not who I am.”

Olsen says his NCIS: Los Angeles costars Chris O’Donnell and LL Cool J have been his role models in the daddy department. “Chris and LL always talked about it — they wrap for the day, and you just drive home because you get to go and see your family,” says Olsen.

He adds O’Donnell, a father of five, also advised him to stick to a schedule from the start.

“He was right about that. You try to get a schedule with naps, with a bath every night, you read to them every night, you try to get into that type of pattern. This world is all new to them, so [it’s good to] get any kind of structure.”